伏安法测定化妆品中熊果苷

Voltammetric Determination of Arbutin in Cosmetics

采用线性扫描伏安法、循环伏安法和微分脉冲伏安法等方法研究了熊果苷在玻碳电极上的电化学行为。试验结果表明：pH2．0的B-R缓冲溶液中，熊果苷在0．86V（vs．SCE）处有一灵敏的氧化峰，在0V有一较小的还原峰。以氧化峰为考察对象，对试验条件进行了优化。在最佳条件下，熊果苷浓度在2．0×10^-7～4．0×10^-6mol·L^-1范围内与氧化峰电流呈线性关系，检出限为1．4×10^-7mol·L^-1该方法用于膏霜类模拟化妆品中熊果苷的检测，得到的回收率在98．0％～100．6％之间。

Voltammetric behavior of arbutin at glassy carbon electrode was studied by cyclic voltammetry, linear sweeping voltammetry and differential pulse voltammetry. It was found that in the Birtton-Robinson buffer of pH 2. 0, a sensitive oxidative peak was observed at the potential 0. 86 V （vs. SCE）, and a smaller reductive peak at 0 V. As shown by the results of further study, under optimum condition, linear relationship between oxidative peak current, ip, and concentration of arbutin was obtained in the range of 2. 0×10^-7 -4. 0×10^-6 mol·L^-1, with a detection limit of 1. 4×10^-7 mol·L^-1. Recovery test was made by adding standard solution of arbutin to a simulated sample of cosmetic cream of known arbutin content, and values of recovery found were in the range from 98. 0% to 100. 6%.